CVE-2026-0990
libxml2: libxml2: Denial of Service via uncontrolled recursion in XML catalog processing
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · January 15, 2026
Updated · September 1, 2026
Description
A flaw was found in libxml2, an XML parsing library. This uncontrolled recursion vulnerability occurs in the xmlCatalogXMLResolveURI function when an XML catalog contains a delegate URI entry that references itself. A remote attacker could exploit this configuration-dependent issue by providing a specially crafted XML catalog, leading to infinite recursion and call stack exhaustion. This ultimately results in a segmentation fault, causing a Denial of Service (DoS) by crashing affected applications.
Statement
This vulnerability is rated Moderate for Red Hat products. The flaw in libxml2, an XML parsing library, is configuration-dependent and occurs when processing specially crafted XML catalogs with self-referencing delegate URI entries. Exploitation requires an attacker to provide such a catalog, leading to a Denial of Service by crashing affected applications.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
CVSS / CWE
CVSS 3.1 · 5.9CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE-674 · Uncontrolled Recursion